“Previously published long-term research, which included a substantial input from Rothamsted Research, has shown that aphid populations in cereal crops can be kept below the level at which they cause economic damage to the crop by using/encouraging native predators and parasites, such as parasitic wasps, ladybirds, lacewings, hoverflies, spiders, and beetles.

“The key to the success of this biological control strategy is to maintain populations of parasites and predators in and around arable fields so if aphids do invade the crops the controls are there ready and waiting. To ensure this happens arable fields need to be managed differently to include wild flower-rich field margins, hedgerows, and beetle banks.”http://www.gmfreeze.org/gmwheatnothanks/alliane-statement-uk-gm-wheat-trial/

We thought GMWatch readers would be interested in several research studies showing the effectiveness of these methods to control aphids in wheat and other crops. The first (item 1) was conducted at Rothamsted Research and involved planting flower margins around the field and installing pheromone strips on canes in the field, both being methods to attract predator insects.

Shamefully, Rothamsted abandoned these sensible and sustainable methods to genetically engineer an “aphid alarm” pheromone into the wheat. It’s an unproven, expensive method that could result in a toxic or allergenic crop (since no toxicity studies have been done on the wheat yet) and at some point the technology will almost certainly be patented, as implied by Rothamsted’s Prof John Pickett.http://www.gmwatch.org/latest-listing/1-news-items/13945

Patents are the sole reason why GM methods are favoured over agro-ecological methods. It is far easier to patent a GM crop than a non-GM crop, as the necessary "inventive step" is clear.

The second study below (item 2) from 1996 specially addresses wheat, the crop that Rothamsted is needlessly genetically engineering. Wheat field margins were planted with Phacelia tanacetifolia, a plant which attracts hoverflies. The result was significantly reduced numbers of aphids in the wheat crop. In the published citation and abstract, the plant is wrongly called “Phelia tanacetifolia” and hoverflies “overflies”, but the meaning is clear.

The third study below (item 3) applied the same strategy to brassica crops, again successfully.

These studies raise the question of why Rothamsted is spending hard-earned taxpayers' money on a GM "solution" to a problem that's already been solved by non-GM methods that are available to all. The answer lies with the (eventual) patent owner.---1. Pest management outlook for cereals and oilseeds based on recent and new research2. Use of Phelia tanacetifolia strips to enhance biological control of aphids by overfly larvae in cereal fields3. Habitat manipulation to enhance biological control of Brassica pests by hover flies (Diptera: Syrphidae)------1. Pest management outlook for cereals and oilseeds based on recent and new researchW. Powell (2006)Rothamsted Research, Harpenden, Herts., AL5 2JQhttp://www.hgca.com/publications/documents/cropresearch/Paper_10_Wilf_Powell.pdf

SummarySeveral recent and current research projects have been developing new approaches to pest management for arable crops. A recent Sustainable Arable LINK project demonstrated the potential of combining field margin management with the use of pheromones to exploit natural control of cereal aphids. Another LINK project has combined the breeding of resistant wheat varieties with improved pheromone monitoring systems for more effective orange wheat blossom midge control. A large EU-funded project on integrated pest management of oilseed rape pests is currently developing strategies that maximise the effect of biological control agents combined with the use of turnip rape as a trap crop for beetle pests such as pollen beetle.------2. Use of Phelia tanacetifolia strips to enhance biological control of aphids by overfly larvae in cereal fieldsHickman, JM; Written, SD [GMW: maybe should be Wratten]Journal of Economic Entomology, Volume 89, Number 4, August 1996, pp. 832-840(9)Entomological Society of Americahttp://www.ingentaconnect.com/content/esa/jee/1996/00000089/00000004/art00008

AbstractOverflies (Diopters: Syrphidae) are potentially important in arable and horticultural crops as biological control agents. Many species lay their eggs near aphid colonies, and their larvae are aphidophagous. Adult overflies need nectar for energy and the protein from pollen for sexual maturation and egg development. Phelia tanacetifolia Bentham (Hydrophyllaceae), a North American annual species that is a good source of pollen for syrphids, was drilled in the margins of 3 winter-wheat fields on a farm in North Hampshire, southern United Kingdom in 1992 and in different fields in 1993. Numbers of hoverflies in yellow water traps, oviposition rates, and aphid densities in these fields were compared with those in control fields. In 1992 in the fields bordered with P. tanacetifolia, significantly more hoverflies were captured in the traps but differences in oviposition or aphid numbers were not significantly different between treatments. This may have been because the wheat matured early so that it was less suitable for syrphid oviposition when gravid females were in the field. In 1993, differences between numbers of adults caught in experimental and control fields were not significantly different. However, significantly more eggs were found in fields with P. tanacetifolia than in control fields and significantly fewer aphids were present in these fields than in controls during the 4th wk of the experiment when many 3rd-instar syrphid larvae were present in the crop. Our results provide support for the hypothesis that a management strategy of providing flower borders for fields can result in more efficient biological control of aphids by syrphid larvae, thus reducing the reliance on insecticidal control.------3. Habitat manipulation to enhance biological control of Brassica pests by hover flies (Diptera: Syrphidae)WHITE, ANTHONY J.; WRATTEN, STEPHEN D.; BERRY, NADINE A.; WEIGMANN, URSULAJournal of Economic Entomology, Volume 88, Number 5, October 1995 , pp. 1171-1176(6)Entomological Society of Americahttp://www.ingentaconnect.com/content/esa/jee/1995/00000088/00000005/art00014?crawler=true

AbstractBrassicas in New Zealand are attacked by the cabbage aphid, Brevicoryne brassicae (L.); the green peach aphid, Myzus persicae (Sulzer); and the larvae of Artogeia rapae (L.) and the diamondback moth, Plutella xylostella (L.). Use of prophylactic pesticides is the usual control strategy against such pests, but the invertebrate predatory community within fields can contribute to pest suppression. Larvae of New Zealand hover flies consume all of the above pests, but the requirement of the adult flies for pollen and nectar may limit their potential in fields where the non crop flora is impoverished. In this work, parts of the borders of three cabbage fields were drilled with the annual plant P. tanacetifolia tanacetifolia Benth. (Hydrophyllaceae) as a pollen source in the spring. Four strips were alternated with 4 control strips (naturally occurring vegetation). Aphid and A. rapae populations were assessed weekly in unsprayed plots adjacent to the 8 replicated areas, and hover fly eggs were counted simultaneously. Hover fly adults were trapped in yellow pan traps that were arranged across the field in transects from each of the eight sampling areas. Border planting with P. tanacetifolia clearly affected numbers of adult hover flies and aphid populations. The potential for this type of habitat manipulation to increase diversity as a component of integrated pest management is discussed with reference to comparable research in Europe.